Overview
- Kwikfit advises turning the heater to maximum toward the windscreen, activating the rear window heater, then switching on air conditioning to dehumidify for the quickest clear.
- The RAC and the AA warn drivers not to pour boiling or even lukewarm water on frozen glass due to thermal shock that can crack windscreens.
- The Galadari Driving Centre describes a roughly three‑minute defrost: set the heater to the warmest setting, run the AC fan on high, use the windscreen heating, then focus airflow on the glass.
- RAC guidance says cleaning the inside of the windscreen with shaving foam can leave a temporary anti‑fog barrier that reduces misting but requires periodic reapplication.
- Motoring groups stress prevention and compliance, urging use of covers, dry towels or thick cardboard secured by wipers, de‑icer and scrapers, with fines reported for driving with obscured windows.